209709074 has 12 divisors (see below), whose sum is σ = 315911454. Its totient is φ = 104406672.

The previous prime is 209709037. The next prime is 209709077. The reversal of 209709074 is 470907902.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 143400625 + 66308449 = 11975^2 + 8143^2 .

It is a hoax number, since the sum of its digits (38) coincides with the sum of the digits of its distinct prime factors.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (209709077) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 437567 + ... + 438045.

Almost surely, 2^209709074 is an apocalyptic number.

209709074 is a deficient number, since it is larger than the sum of its proper divisors (106202380).

209709074 is an frugal number, since it uses more digits than its factorization.

209709074 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1417 (or 938 counting only the distinct ones).

The product of its (nonzero) digits is 31752, while the sum is 38.

The square root of 209709074 is about 14481.3353666021. The cubic root of 209709074 is about 594.1175856581.

It can be divided in two parts, 20970907 and 4, that multiplied together give a triangular number (83883628 = T₁₂₉₅₂).

The spelling of 209709074 in words is "two hundred nine million, seven hundred nine thousand, seventy-four".